RapMan

Hi, is it ok to drill the hull or any part of the fibre glass structure for modications? I'm looking at playing around with some rudder and trim tab designs. Will drilling weaken the integrity or the fibre?

Thanks
Veren

Nocturnal

Actually no. Once the glass is laid and dry the hull should be like one whole unit. If you are going to drill I would use brad point bits and don't press to hard, let the tool do most of the work.
Good luck...

green-boat

Fiberglass can be drilled but care must be taken as to not to chip the edges. Use a small brad point drill bit to get things started and follow up with a "Unibit" to get the hole to the desired size. Lite pressure and a good speed is the key

brettos01

Cover the transom with masking tape, markout any screw holes you need to make then drill with a high speed drill, with little or no preasure, the tape will help prevent the gell coat from splitting.
Always check that your holes are in the right possition twice before drilling any holes.
When the holes have been drilled, I have found that a little resin covering the inside of the hole is a good idea, then drill the hole again to bring it to the right size. This helps reinforce the hole and reduces the risk of splitting the transom. I also glass an alluminium washer inside the transom wall, the right size for the part and this reinforces the exit point.

Hope this helps, Brettos.

Merry christmas.

LtDoc

Veren,
Short-n-sweet, yes, you can drill/saw fibreglass without weakening the structure. There are "but"s though! The idea is to not produce cracks resulting from the drilling/sawing. That means very little pressure is used on the drill/saw (fine teeth on the saw too). 'Hurry' makes for problems. There are various types of drill bits that will work with fibreglass. What they are called just depends on where you live. Basically, starting with a smaller than required bit, then filing the thing to the right size is just one way of doing it. The masking tape to prevent chipping of the fibreglass is a good idea, but it isn't fool-proof by any means, still requires care and no hurrying. The idea of resining the finished hole is also a good idea. Again, be careful. And have fun....
- 'Doc

PS - Nothing 'new' in the above, just a different way of saying the same old stuff. Last bit of advice! If it finally drives you crazy, use a chainsaw for the holes.

RapMan

No chainsaws yet, I'm having too much fun . Thanks for all the tips guys. It may be old stuff
but valuable to a first timer. I guess with fibre glass it's "easy does it nicely".

Veren

LtDoc

Veren,
I guess what I should have said was "nothing 'new', just the same thing everyone else already told you". I am definitely not any kind of fibreglass expert! I'm just glad no one can see what I can do to a perfectly nice fibreglass hull (and I ain't telling!).
What it comes down to is the tools you have and how well you know how to use them, or how not to use them, as the case may be. No one knows all this stuff to start with and unfortunately some of us have to learn the hard way. Hope you're not one of us. The thing to remember is that almost anything done wrong can be 'fixed'. And when you stop to think about it, those 'fixes' are the most fun. [The thing about 'stopping to think about it', is that you also need to start again, you know?] And with that I'll shut up...
- 'Doc

RapMan

Doc, I wouldn't exactly say that the fixing is fun but you're right that's when the learning ( and the great ideas ) come and I'm also definitely one of the "hard" learners.